My CPA firm (www.badgercpa.com) specializes in start-ups and we work closely with Copp Law Firm (http://texasllcpros.com/) when determining the appropriate entity structure. Feel free to reach out if you have any questions.
Dave, it seems many topics come up that need multiple perspectives (Lawyer + Accountant together to complete the picture). for example when setting up company structure, depending on how you set it up; you could end up with double taxation. So this plays into the documents that the lawyer needs to vet before you start looking at the VC route. Thanks for your comment.
I think your search should take into consideration firms that have experienced people that have worked in startup businesses themselves (as they will understand the actual practicalities of small business finances - being at the coalface of a cash tight business beats the theory any day!). This is crucial in building a solid relationship and trust that the accounting firm can best provide the guidance needed for your firm. It is also particularly important that they themselves have been through fundraising, either in a startup or as advisors to startup; ensuring they understand the needs and wants of a potential investor rather than simply producing cookie cutter one size fits all plans that will fail investor due diligence. My firm, Nuvem9, in Uk is based on these principles and I'm happy to offer any advice as you continue your search for a firm in your locality.