What can I do for some pre-launch SEO on my E-commerce site?

If you really want to do something before you launch your site, you should give ads to different places and sites. That will help you to gain some traffic from before.

Thanks. I am about 2 weeks from launch and will start this from next week.

I will be going with Google for now, and have just got in touch with some targeted forums for some ad space too...cheers!