Hello there! Would you mind giving me information about decent SEO firms which are working with google? Please let me know
Depends on your niche and project I guess. Lots of good SEO places out there check out http://seovb.com or http://brokensnooze.com I guess if you want some
The best SEO firms are very expensive, usually out of range for most people. You have to be willing to spend at least $5k a month. If you are looking for "cheap" link building, don't expect quality backlinks. You would be better off making your site the best in its niche and doing the link building yourself. Everything you need to know can be found by spending a lot of time reading these forums - and ignoring the posters who are trying to sell you some cheap services. If you are looking for help in optimizing your site, then there are probably a lot of users on DP who could do a decent job for you for a reasonable price. Ranking for competitive keywords requires a lot of off-site work (link building).
there are thousands of companies who will do this for you, you are best off doing it yourself until you understand it enough to be able to accurately judge it people you later pay to do it are doing a good job or not.