hi there,
i do a lot of road cycling, and want to get a fixed gear bike to train with because i've heard they are better for training than my racing bike and i would like to know what i need to know when looking at bikes and anything else that i need to know to get myself started. any tips would be great to help me out

Well, since you're familiar with bicycles due to your roadie background there's not much in ways of tips. A lot of the roadies at my LBS ride the Specialized Langster and love it. But I think you're making this too complicated however. There's not much to know when looking at the bikes. Most bikes will have rebadged formula hubs, most will come with a Sugino RD2 or likewise crankset and a velocity style wheelset. You can go yard sale shopping or check out some thrift stores and find a old steel road bike and do a fixed gear conversion.

1. Get one that fits, and is drilled for brakes (if you're only using it for training).
2. Ride it.
3. **********
4. Profit (due to your hardcore training).

But seriously, what's your pricerange and do you care about steel versus aluminum? How much cash you have to spend, will greatly affect what bike you should get.

I'm not to familiar with the aluminum offering, but I'll just pass along the following:

Good steel options:
Wabi makes amazing bikes, and if I had the cash ($7-900) I'd go for that.
The Surly Steamroller is a great bike, costs about $720 for complete.
For a lower priced, but darned good, trainer bike the Mercier Kilo TT is more than worth it's price.

As far as aluminum, there are plenty of options but I'm not too familiar with them all.
One of best-priced offerings I've seen is the Motobecane Team Track ($800).

+1 to all of the above.

but a low gear and spin your ass off