I agree with the flash, you need to get rid of it. I know a few years ago it was harder to SEO a flash site but not sure about today. The average person won't wait more than 5 secs for a site to load to view it. All you need is some patience. A new line is difficult to start going. There are so many new independent clothing lines starting up that everyone thinks its easy to get into.
Check out this 9-year:
Caine's Arcade on VimeoHe never gave up and ended up having one person organize a flash mob to help him out. He never gave up on his creativity or dreams.
You need to keep everything in one site. The redirect to a new page for the product with a higher price than on the previous page is a little annoying. Its kind of like going to a store and expecting to pay a sale price for an item and then the cashier says this isn't the correct object even though there is a sale tag on the item.
Have you tried flea markets? Even if you don't make many sales its a good way to start getting the word out about your shirts in your area. The middle schools and high schools around here sell ad book space. Every year they come out with a little booklet of coupons and information about business's and sites to help raise money for sports and what not.
As for FaceBook: Have a monthly drawing and give away a free shirt or even weekly if your costs are low enough. Use Booshaka on your facebook page and encourage people to share, like, and comment. The highest person of each month gets a free shirt. Social Media is all about interacting with others. Even if you have to share your own stuff on your personal page, if your friends like/comment their friends may see this on their walls.