If this is a government job then they will want you to have:
1) Commercial General Liability
AND MOST LIKELY (Exception might be made for a subcontractor who would be covered under the general contractors bond)
2) Contractors Bond
As far as the liability insurance I am sure that the previous links that I provided you with will offer you the best premiums.
Regarding the bond you will need to know how much the bond needs to be for. The bid specs should tell you. It may require a bid bond and a completion bond. Usually these are a percentage of the overall job.
I am in Ohio but work with a insurance company that is located in Lansing, Michigan called Auto Owners. I know that they are a good company and that they provide bonds for contractors. You can go to their site at: http://www.auto-owners.com/ click the "Find An Agency" link and look for a local agent in your area.
Another good bond company is CNA Surety you can contact them at 1-800-331-6053
Again I would use the previously provided links to get the best rates for the links for the Commercial General Liability quotes: When using these links I would make a request from each of the services. It's free, secure and ther's no obligation to buy. You would have to literally go to 50 or 60 agents to get the same amount of quotes from different companies.
Let me know if there's anything else i can help with.