Regarding trademarks in the U.S.

My friends and I have launched our own business (an apparel company) and we’re looking into the various trademarks and copyrights we need to deal with. The copyright process has been fairly easy: Just submit the artwork that’s going to appear on our shirts with a simple form and a check for $45.

The trademark, on the other hand, has me utterly baffled. What exactly are we supposed to trademark? Our t-shirt line’s logo? It’s name? The online form for trademarks is pretty straightforward, but I can’t figure out exactly what I should be sending to them.

I also know that you can trademark anything, but registering that trademark with the government confers certain benefits. Is doing so actually worth it and likely to come into play at some point?

Any advice from those who have trademarked something or any IP lawyers are particularly welcome.

You can look for the answers at the Trademark office home page: http://www.uspto.gov/web/trademarks/workflow/start.htm

They even seem to have an online application form.