Bankruptcy help

I live in San Francisco, California. Generally speaking, how much does it cost to retain an attorney to handle a bankruptcy case? Does the court impose any fees for filing? When an attorney is retained, is there an obligation on their part to deal with the clients creditors? By that I mean, writing/calling the creditors, and following up on any subsequent threatening calls and mail from creditors. Also, I would like to know about the do-it-yourself kits that can be downloaded from various web sites. How easy are they to understand and fill out? Are they readily accepted by the court? What problems might I encounter if I try to do this myself? I appreciate your advice. Thank you.

attornys in FL want $1500 ...way too much for me.
Paralegals won't do a 13 anymore...so I'm going to do it myself. I'm thinking about the site 77law.com...but still thinking about it...it's $140.