3.) http://www.oneacross.com gives you a crossword tool where you can type in "???me" and it returns all words that match that pattern.
Also, just checking out potential competitors will give you ideas as to what they are using and what might be good. You probably want to buy a domain that is easy to market, and getting good keywords is critical for search engine placement.
It is also good to keep in mind that if someone searches the internet for "thisword", thisword.com will usually get the best search engine placement. With Yahoo!, thiswordthatword.com will not register as having "thisword" in the domain, however thisword-thatword.com will register "thisword" as being in your domain name. (which is a good thing)
Are you wanting specifically a .net for the extension? I'de advise to have the .com (if it's a commercial site.. which it appears it will be for webdesign biz) and I'de advise you snag the .net so your protected. (own both.. build on one & protect yourself by owning the .net) We have Earthboard.com 4sale.. $75
how about desing.com ? You could make a cute animation showing how it's not "design.com" and how folk's'll "sing" with joy with your services and attention to detail... and all the typos you'll pick up from design.com anyway...