multiple domain names on same site

[happyhippo]

I'm considering registering a second domain name to my site - something like= guitar-lessons.com or guitar-tab.com, For higher SE ranking when people search for those terms. I already have my site registered in all major search engines with a domain name - so will registering it under a second domain be bad or good for my rankings?

[waterbug79]

Generally speaking, that would be a bad idea. The search engines would treat the two domains as two different sites, and your pagerank would be diluted, etc. If you want to try to rank higher for certain terms, a better idea would be building incoming links with those terms in the link text rather than registering more domains.

[incrediblehelp]

You can own as many domains as you want, but don't duplicate a website under each. Simply 301 redirect the "secondary" domain name to the primary.