I know that there are a couple home improvement stack exchange sites in existence already. Would/Should we seed this site with questions/answers from the other site so to help it grow? Obviously when you have different sites on the same topic, there will be too much noise. I know the focus should be on drawing in DIY enthusiasts (like SO did for programmers) but it seems that if we seed the site then it will increase the potential to show up more in Google searches.
There has been some discussion about this in Question 64. As Robert has pointed out, it is important that the questions reflect actual problems that people are having. “Seeding“ in the form of asking questions you don't personally care about is bad. The way to grow the site should be to bring in more people so that they can ask questions they care about also.
Of course, nobody would know if you ask a question about a prior project (where you have already solved the problem in some way, perhaps not to your satisfaction, but moved on) or a potential future project (where you have invested time and effort into research and have a clear, specific question). It's fine to look at other sites for ideas (just as you could be reading web sites about sheds just for fun and then start planning your own shed and ask questions about), but don't import a corpus of questions wholesale.
I think it is a red herring to think about building a site so that it will show up in Google search results. That will happen organically as the site grows. The focus right now should be to build the community: we have a core of people, a core of questions and answers (from the private beta), and new users and questions have started trickling in. Page views started to slump toward the end of the private beta, but now they are already climbing again, so I'm not worried. But the important thing right now is to continue to bring in enthusiasts. Tell your friends.
While you shouldn't make up questions, it's perfectly ok to ask about a problem you've had in the past, and even to answer your own question.
So if there was something you got stuck on and there's not already a question about it, ask it, answer it, and save someone else the headache. The "Ask a Question" page even supports posting an answer at the same time you post the question:
The key thing is that you have a specific scenario in mind so that you can write a good question, respond to followup questions, and select the best answer.