Hi C.,
For an interpreter, rates are different depending if they are an employee or independent contractor. Rates vary in the community for actual interpreting. For a NON-certified interpreter, brand new out of college they typically get 16-25/hour depending on where they work and what the agreement is.
Teachers in the world are typically 25 and up /hour for tutoring services and that is a VERY reasonable rate if they are licensed.
If this is a friend and you are working with, they will/should probably give you a decent rate, teaching sign language and OTHER developmental skills (not sure what that means so not sure what to say there) you might be looking at 25+/hour.
The question I have to ask is: Why are you talking about pay? Just food for thought, if you are going to be paying someone you could also consider spending the same amount of money for some exceptional DVDS which you could learn from and eventually your daughter if you are interested in her watching tv at some point. Signing Times is the one most folks I know who use DVDS us.
p.s. I'm a certified sign language interpreter and have my master's degree in education. I taught ASL for 6 years and now work in the interpreting field. Im NOT interested in providing classes, just letting you know where I'm getting my numbers from. :)