Wishlist member. Bit on the expensive side but worth every penny, and once you start using it you will never want to see any cheap and half-arsed alternatives again.
Make sure to watch the tutorial videos though as unless you're technically very savvy there's somewhat a learning curve, especially when it comes to advanced options.
Btw. I do realise that Wishlist may be a bit too much for your needs right now (after all your site is going to be free and only have one membership level), but you also need to think about the future - having a scalable system in place from day 1 eliminates tons of headache later, say if/when you decide to introduce paid membership, etc.