Bicycle Mechanics - Need more fitting bike to my body

The bike store where I bought my bike has closed.
I'm 6'-4", weigh 255-lbs and need help fitting me to my giant boulder se with a 23-inch frame. My first rides didn't last much longer than 30-minutes due to my hands going numb. So I switched the stock straight seat post for a Kalin with a 25.4mm setback and the stock seat for a Serfas with longer rails, also set back to the stops. Rides last nearly an hour now, but I'd like more time on the bike.
The bike came with a 2.5" riser neck stem that is about 4.25" long. A few searches at local stores hasn't come up with anything higher or longer.
I feel as though I'm still leaning to far down or too close to my body. Don't know if stretching out further or higher would be better, but something more needs to be adjusted or changed.
Any ideas would be helpful.

There are a number of fitting independent gurus spread out all over the USA. Some work within bike shops, some independently at home, in small studios, or at fitness centers with spin classes.

Scientific fitting is very in these days, with various systems in play, using high tech concepts like video & computer motion analysis to obtain precise fits. Personally I'm not sure these methods yield better results than the eye of an experienced fitter or coach, but they'll at least spot problems and get you fairly close to where you should be.

If you search bike fitting on the net, you'll find guides, tutorials, charts and fit system marketers, whose sites will list their trained fitters by location. I suggest you start with some of the self help tutorials, and if that fails contact a fitter near you.

Are your bars flat? if so, have you looked at ergonomic grips, lots of companies make them, Ergon, Specialized, Bontrager etc, they can help with hand numbness

Start here.

http://www.peterwhitecycles.com/fitting.htm

This article is a classic from a very experienced "cycling eye".

If hand numbness is an issue, be aware that often it has little to do with direct pressure on the palms. The hand's nerves pass through narrow spaces in the wrist, and poor hand/wrist alignment can press on the nerves, or affect circulation. Look at how your hand aligns with your arm.

If the wrist is bent back, or twisted, or kept in an unnatural position for long periods you'll get hand numbness. Changing hand position or flexing the hand and wrist from time to time helps, but the best solution is finding a more natural hand position.

Start here.

http://www.peterwhitecycles.com/fitting.htm

This article is a classic from a very experienced "cycling eye".

Great link.
Bookmarked.

plumb line thru the BB, divides the cockpit in half ,
back of thyat line, ;setback is dealing with thigh length and weight bias .

then from the front of the BB line you have the rest of the top tube ,
and the stem extension ..

the parts of your body proportionally influencing that,
are arms and torso length.

jimc101,
Bar has a 1.125" rise and angles back slightly towards the seat. Ergonomic grips would certainly help, Thanks, I'll be looking around for those most definitely.

What I meant by flat, was flat like and MTB, or drops like a road bike, as the ergonomic grips only work for flat bar bikes

While fit is important some of the issue, if you have not very athletic up to now, is just time in the saddle. Try doing more short rides with stops in between. Such as ride somewhere and then go into a favourite store and just schmooz for 15 to 20 minutes and then ride to some other store and schmooz for another 15 to 20 minutes. Soon you'll find that your schmoozing times are becoming less and less and eventually you'll be fine to ride right past one, two or all the stops on your ride. This will happen for two reasons. First your core muscles will tone up and carry more of the load. Secondly your arm and wrists will tone up and be happier to carry what your improving core section still can't support.

Being able to ride for an hour before the ergonomics of your bike bite you suggests that the fit is pretty darn close and you just need to ride more and take the sort of short break(s) mentioned above mid way through the ride or about every half hour of riding time for the next while. If the fit of your bike was truly bad you wouldn't even be able to ride for an hour at a time.

jimc101,
Bar has a 1.125" rise and angles back slightly towards the seat. Ergonomic grips would certainly help, Thanks, I'll be looking around for those most definitely.

before you spend a penny on new stuff, even stuff as cheap as a pr of grips, try an experiment.

Close your eyes and hold both hands out in front of you at shoulder height and width. Don't think, just do it. OK, open your eyes and look at the natural angle of your hands.

Now sit on your bike in riding position & look at your hand wrist and arm.

Odds are the hand is bent out following the angle of the bar, and bent back on your wrist slightly, not at all like what you did before. Plus, most of the weight is probably on the heel and there's almost no weight on the well padded base of the thumb.

If that's a fair discription, rotate the bar almost 180 degrees (no need to remove it) so it bends down and forward slightly. See if that gets it closer to what you did with your eyes closed. Tweak it until you find what feels best, then reposition the levers accordingly and take it out for a spin. Odds are your hand will hold up better, and if so, you can then experiment more until you have the best spot.

If you have a bike where you're really leaning forward, that might have something to do with it. I think hybrid or a bike with a touring frame might help with an appropriate seat (saddle). There are sites like selle royal that have graphs to show which seats you can choose for which position.

Or maybe doing weights for your arms might help.

Also, higher handlebars might help maybe like these: Brave Stiffee handlebars
http://www.chainreactioncycles.com/Models.aspx?ModelID=35905