Humm, are you specificially asking about contact forms in WordPress or about forms in general?
For forms in general, knowing php is going to serve you well. Once you’ve built a few forms, you’ll have a toolkit of code that will let you build them quicker.
For WordPress…. that’s jumping into the deep end of the pool depending on what functionality you need. If it’s just a contact form, then it seems like Contact 7 has a lot of flexibility.