One thing about the funner corkscrews sold online is that they run more than a few dollars. I figure this is because sellers (rightly -- usually) think people who drink wine have disposal income, and are willing to put some of it toward wine accessories. Hence, the price tags of fun corkscrews.
Still, you can have a lot of fun with cheap corkscrews like this one.
With that said, here are some tips for finding quality, fun, cheap corkscrews.
Out there in the "real world", you can find fun corkscrews if you know where to look. "Where to look" includes stores that sell other people's junk which you may find to be treasure. Namely, this type of store is one that deals in "junk" or "home good recycling". I would not expect a thrift store to typically deal in corkscrews.
You may luck into a fun corkscrew at a dollar store. If you do, I would not expect it to be a long-lasting, durable sort of item.
One place that could yield you a unique, fun item is a yard sale or garage sale. Pick a sunny Saturday and hit a few. You may find yourself the new, proud owner of a fun corkscrew with some history on it.
Most of all, be sure to check eBay. If that place was not born to sell kitschy kitchen items cheap, I do not know what other purpose for which it exists. Happy uncorking!