First of all, great site! It flows well and has nice pics, colors and layout.
1) Your homepage text is too light and small for the beige background. It makes it difficult to read.
2) When a customer clicks on something to purchase and they are sent to paypal, it gives a sense of insecurity in completeing the transaction. Also, many people don`t have paypal accounts and will leave your checkout when they realize they are being sent there. I recommend getting a merchant account and an SSL certificate with a cart system. I use osCommerce carts with my customers... it is the safest and userfriendly system out there.
I am curious. Since you get your products from Brazilian-Bikinis.net, what is preventing the customer from buying directly from them and cutting you out of the equation?