You can use free tool like overture or pay for wordtracker Google also has free keyword research tool that you can use
I don't think you can guarantee anything on the Internet. Getting the right keywords is like building a house on good foundations... You can get a great foundation but build a real crappy house on it, or... You can get a crappy foundation and build a really nice house on it... ...but the house ends up sinking into the dirt!!! Do extensive keyword research. Find keywords related to your niche which provide traffic but are not too heavily saturated. Then build your site and include these keywords in the page title and throughout the site text, but in a non spammy way. You don't have to cram the page full with your keywords, but sprinkle them throughout the page if possible and include them in the header tag a few times if possible. Then include the keyword in as many quality incoming links as possible, but try to alternate or add a word infront or a word after your keyword occassionally so your links don't all look exactly the same.
yes content is the king, but what about you having good content, but not proper keywords how can you be included in SE.
whats the proper no. of keywords to put in the front page title, i heard if too many is bad, keep it under 6 keywords??