I got my 55 for sixty dollars from a lady who had gotten a divorce (it was her husbands.
has a great filter, lights, and all that) on craigslist.
You can get great deals if you just look.
But you may want to find a 10 gal minimum for your fish as soon as possible. They are much happier when they can swim alot.
Check out garage sales and thrift stores in your area. I got alot of my deocrations brand new at a thrift store at a quarter of the price.
I also got a 5 gal for 5 bucks at a garage sale. You never know what you will find.