Yes, When your choosing a domain for any business website, always pick .com domains. kingsizevps.com/ - king Size VPS | makeanysite.com/
you may also check third party websites to get suggestions and you may get some promo codes also like, for goaddy etc you may check http://domainpromocodes.com/coupons/godaddy/ for go daddy, you should also consider other than .com because you may not get your desired domain in .com
Its not l true that .com do well in Search Engine Rankings than a .tk domain. .com just helps to win the trust of the visitors
This also depends on the country. People from Holland (the Netherlands) usually have more trust in .nl domains than .com domains.
Everyone will give the same answer which is .com because .com become and preferable and acceptable domain by most of search engine . That is why people always go for .com domain only. But do notice that currently .co and country domain name value start increasing. Fast index or not is not matter of your domain extension, it more toward that how you get your site get crawl by search engine.
Since you brought it up, Foro, I have a question. In the earlier days while the internet was becoming a household thing, .com was most popular, and used for most sites that weren't using .org, .gov or .edu - the .net was almost always used by internet service providers. So my question is, is the .net still mostly for providers of internet services, or is it pretty open and available for anyone and everyone to use for their domains now?