How can i choose the best Domain name?

Nowadays it's not easy to found a Domain name with one or two words and expecially with .com or .net tld. Very hard to find are 2, 3 and 4 letter domains (LLLL,NNNN,LNLN and so on).

So i can found a new domain name to register?
On internet there are any Domain Suggest tool that you can use to found a new domain name or check for expired domains too, but this one are usually worth more than a new domain to register.

Are new TLD good to register?
Even if google say that new TLD's have same chance to be indexed of older one i have seen very few domains in first pages result on Google, Bind and other search engine. Of course 1├Čone word domains are good to register. The most important thing at least will be the content of your site.
Keep in mind that older domain (expired one or if you buy an existing domain from owner) could be indexed fastly on search engine respect to a new domain.