If you have that C and Java experience, pick up Head First iPhone ProgrammingHead First iPhone Development (not associated with the book) and you'll be able to pick up the basics fairly easily. If all you're going to do is create an app that displays a UIWebView and loads a web page, you'll be able to figure it out in a matter of days.
If it has to do more than that the there's a fairly steep learning curve, but that book will teach you enough to actually know what you don't know. At that point you'll be able to look things up in the documentation and make sense of them, create decent Google queries that will return what you actually need, ask decent questions on Stack Overflow that will that will result in good answers that you can understand.