I just went through this for a product I'm working on. I spoke to a lawyer here in Toronto, who said there were basically two things I needed: an IP waiver, to protect my intellectual property (a.k.a. my idea) and an NDA, to protect the sharing of information.
Basically, if someone works for you, you want to make sure that you still own the idea, and your employee can't take the idea and create it themselves. You also want to make sure they don't leave your company and take your clients, or your other employees, with them. That's what the IP waiver is for, and mine included a limited non-compete that protects for the latter issues.
You also want to be able to talk to people who may or may not work for you about your idea. An NDA is a document that says that the person signing it will not tell anyone else any information that they acquired from you, and isn't available to the public.
Besides those, once you have a product, you may need to file for a patent, or for copyrights. There are lawyers who specialize in that.
In looking for a lawyer, make sure that either they or their firm can provide a lawyer for all your needs. Going to a single lawyer will probably be problematic in the long run, as you won't be able to use the same lawyer for everything. (As an example, patent law is pretty specialized, and lawyers who focus on that tend not to do other forms of law.)
The documents I had drafted (IP Waiver + NDA) cost about an hour of work.
First off, I am not a lawyer, I just work with a lot. At the risk of oversimplifying, for a "typical" web service startup, the major benefits of working with a lawyer at an early stage are:
These are somewhat intertwined. Regarding your question about would the same laywer handle everything:
For intellectual property, you definitely want someone who specializes in the internet and software space.
Now here is where I'll probably get hate mail: While there are general practice legal firms (often larger) that cater to startups, and many will even defer fees, I disagree with Elie's advice to use a "one stop shop" firm. They are expensive and the quality of the work is heavily dependent on the associate (jr. lawyer) you get. How expensive? On the order of $10-15K for just the basics.
Better to work with a specialist attorney at a boutique firm. Rates are much better (can be 30-50% less than large firm) and you will generally work with an experience partner. Of course, finding the right one is the challenge.
If you want to get some really good info at NO cost contact these folks.
They form entities and have registered agent services etc but what I really like is that you can call, get a human and just visit with them about what is best without paying anything or being obligated to buy. Sure they want you to do business with them, but they first want to educate. They are very good at hands-on, human-to-human help.
If there are items that in fact need an attorney's involvement, they'll tell you. But not EVERYTHING about creating an entity has to go through an attorney.
Laughlin Associates - 888-273-8152