Hi Jeff,
Check out
Boston Datacenters. I've been using them for years. They have a great e-commerce package using osCommerce (my favorite as well) for about $35/mo. The package also comes with lots of extra scripts for just about anything you may want to do with your website.
For payment processing, I use Global Payments. I like VeriSign's Payflow packages. It comes in two flavors: a less expensive option where the final payment is handled on their server, and a fully customizable solution that costs about $800/yr.
Let me know if I can help with anything else. Good luck in your search!
Jen Gatza
Automaton Engineering, Inc.
www.automatonengineering.com
(352) 688-5151
jen@aeimail.com