There are places where you can get cheap/cheaper Second Life avatars, it's just sometimes hard to find them. I must admit, usually the better-looking ones are more expensive in comparison.
I don't use Second Life a lot, but might get on it every nowand again. Here is the avatar I use:
The only reason I was able to get such an avatar was because I hopped on a... I think... few years after I made the account, when suddenly this kind guy came by and was helping me out to understand the surroundings and settings. He gave me some linden (SL currenceny, for those who don't know) to help me get started to get an avatar I wanted myself.