I'm sure you get this kind of thing a lot but I felt like you all were the best people to ask. I've been riding road bikes recreationally for over a year, but I've pretty much been stuck with bikes my parents stopped using 20 years ago or bikes they found at yard sales. I had an old schwinn and an old peugeot, both were a bit too small, but they kept me entertained. Now I'm trying to get more into biking and I've been looking around craig's list for awhile but haven't had a lot of success, maybe because i'm often afraid of getting ripped off. Basically what I want to know is, what kind of bikes are worth in the $125-$250 range and how do most people feel about brands like schwinn, raleigh, ross, nishiki, etc. Any help would be greatly appreciated!

If you're taking about Craigslist you should tell us where you live. Prices depend on what market you are in.
Here in San Francisco 125 will get you a half built fixie conversion and 250 will get you a shiny Raleigh 3-speed that needs new EVERYTHING.

I live between philly and delaware so I've been checking out both of those, but I go to Penn State so I've also been looking at State College. I feel like there are a lot of people posting bikes for more than they're worth, but since I don't know a ton about the bikes, I can't say that for sure.

Also, not sure if it matters, but I'm somewhere between 56 and 58 cm I believe

The most important thing (like buying shoes) is to get the size about right. There are lots of on-line sizing calculators that will be adequate to put you in the right ballpark. That's good enough. Aside from that, I'd make sure that everything works and I suspect that you'll be OK. If you're planning to ride the bike on campus I think that you should either hold out some money for a GOOD lock or just buy a POS bike that you won't mind so much when it gets stolen.

With that much money I'd look for good deals on steel downtube shifter bikes. Look for Centurion, Bianchi, Trek, Nishiki, Giant, Fuji, Miyata and any other name brands. I typically stay away from Schwinn, Huffy, Murray, and other cheap bikes. Schwinn makes some nice bikes, but most of them that people post are crap.

Downtube shifters usually indicate a higher quality bike than one found with stem shifters. Also, if you don't know anything about the bike ask people in classic and vintage. They can give you a quick answer. When looking at the bike, check to see if it's in good condition. Don't get a rusty bike. Buying a bike with dry rotted tires, cables, and chain could cost you $100 to repair, and wouldn't be worth it unless you could DIY and get inexpensive parts to repair it.

+1

The C&V guys have walked me through many a CL post and have helped ID a 79 Schwinn I'm restoring and a 93 Diamondback I got for a steal. Don't buy an old one until you go there!

Excellent advice!!

make sure the tire hold air, slight rust on a frame is not a big deal- but rusty chains will probably need replacement.
Take the bike for a quick cruise and see if it tracks straight, shift through all the gears and if the brakes work. Hold the bike and spin the tires to see if they're straight, or if they wobble.

Awesome advice, thanks everybody!
For the online sizing calculator, anyone have one that they would recommend?
I've got a decent u-lock and I had my bike up at school and never had any sort of problem with it so I think I should be fine in that department, plus this year I think I'll keep my bike in my room unless I'm at class, just to be safe at night.
I posted this on c&v a bit after I posted on here because I thought I might have posted in the wrong forum but you've all given me great helps, so thanks for that!

why don't you save a lil bit more and buy something new from bikesdirect.com ? there are some decent bikes for $400

like this one:
https://www.bikesdirect.com/products/...agesport_x.htm

aluminium frame, sti shifters, shimano 2200/2300

btw I just bought a much ****tier bike than this one for $400 as well and I'm pretty happy with it.

That looks awesome, unfortunately though, it's all sold out in my size. I'm either a 56 or a 58. By the way, if I had to make a choice between the two, do you think it's better to go for a little bigger or a little smaller?

Smaller frame reduce the incidence of testicle to top tube interfacing.

Competitive Cyclist has a pretty nice fit calculator here.

Heheh I hadn't thought of that, makes sense to me though, I'll keep that in mind.

Thanks for the link to the calculator, I'm gonna try that out right now!