Greetings everyone.

I was wondering about the internet doing research and I stumbled on another question from this forum and started kicking myself for not having found this site sooner.  So hello everyone, this is my first post.  I hope that we can help each other in our endeavors.

I am starting an advertising agency (well it's actually just a few friends of mine tagging along for the ride), and have several questions that I would like some input in.

1.  Sole proprietor vs. Partnership vs. LLC?

I can start work ASAP if i set it up as a sole proprietorship, or partnership.  Do you guys suggest going with an LLC for an advertising agency?  I would have clients sign papers stating that they are full satisfied with the work I've done and are willing to move on to the next step in the process EVERYTIME I complete a step... which should alleviate any possible issues with being sued from their side.  Should I really worry about getting sued with a business that does not offer a physical product, or have employess?

2.  If I'm claiming all of the income through misc income (because I'm a sole prop at the moment), do I need an EID?

3.  I have a serious problem with NOT having a physical location.  I feel that not having a location makes potential clients see me as not serious about my work.  Is this a serious problem?  Am I overthinking it?  Do you feel that businesses are expecting startups to actually have a location in order to take them seriously? 

Those are my questions at the moment.  I have many more, but I will wait to get answers for these questions first before posting more to see how active the forums are.

Here are the things I've accomplished/made in regards to the business:

-Business plan (informal, but it fits the type of agency I want to create)

-Business cards

-Website (hosting and domain for 10 years)

-Stock documents (about 10 pages of misc. documents I will need when dealing with clients)

-A small amount of money from people who have tried me out (not a lot of money at all)

Things that I haven't done, but think I should:

-EID

-Name registration with the state

-Plan to get clients (this will be a different topic altogether)

What do you guys have to say?  This is all overwhelming for me, but I have a very positive view on what I want to accomplish.  I've also met with respected professors from well-known colleges that tell me I'm on to something good, and can potentially be very lucrative if I manage to play my cards right before anyone else gets to it in my area.

Honest comments and criticisms please.