I recommend you read this book: http://www.google-secrets.com - he sends the latest updates for free when something changes or he has new findings.

It'll help gain some knowledge so when search engine optimization companies try to blow smoke up your rear you you'll know.

In most cases small companies can't afford to pay big consulting bucks and doing the foot work (sometimes a lot) may end up being less expensive... especially when starting up.

good luck!