What kinda clothes are you looking for? if you are just looking for shirts and whatnot you can't go wrong with ebay. I buy some clothes from other sites, but for cheap stuff nothing is better then ebay! good luck
The thing about buying clothing online is that shipping itself can make out to be anywhere from 5 - 30% of the original cost. If you are really low on money, I would suggest just looking for blowout sales and coupons. If it is like expensive Nike shoes or something that you are looking for then they are right, ebay is probably your best option.