Let's say you are an engineering company with the name Bluebird. Bluebird.com may be taken, so you could try bluebirdengineers.com, bbengineers.com, bluebirdinc.com, bluebirds.com, blue-bird.com. If you have a product like jam, and jam.com is taken, you could try jamhut.com, jamjars.com, jamplanet.com, jamworld.com. You get the drift. Use a .com.
ccTLD are good if you have strong content based site or a good budget to work on promo. A little work on SEO will also be helpful.
Overall, if you targetting region specific, ccTLD can be the best deal, but what about down the line, say after 5 years? What you not like to grow? Would you not like to expand biz? Then, will you take risk of changing domain (ultimately brand?).
So, think wisely now and take decision smartly!
Regards,
Dipen