Genesis and other questions

Hey Warriors,

So I have my niche nailed down. Did my keyword research. Thinking of buying one of the beautiful Genesis themes from Studiopress. I have (lightly) designed some (crappy) sites in the past using Dreamweaver, but honestly the learning curve is ENORMOUS for DW and my trial is running out anyway. $400 is way too expensive for me right now.

So. On to the questions:

I can use Wordpress to design my sites, right? Instead of Dreamweaver, is this correct?

If so, will I be able to easily manipulate my sites using Wordpress? Is there a lot of room to tweak my themes?

Can I use third party plugins like Aweber with Wordpress to drop in an opt-in form? Will it look ok? Can I center it in a sidebar?

Can I add a forum into a Wordpress theme? Anyone know the cost on this and how much work it takes to set up?

And finally... What is the cheapest way I could get an entire site designed if I were to just bypass DIY altogether? Any suggestions?

I want a good looking site and I have a vision, but a very limited budget. I want to get things rolling but I'm stuck looking at so many themes it's making me dizzy. Too many options. And I'm worried about getting bogged down with the tech side of things.

Obviously I have my content on lockdown given my profession, but the design and tech stuff is making me nuts.

Sorry for all the questions. Just want to do this right.

TIA

n.