O’Reilly has announced it will be holding four iPhone development workshops in locations across the U.S. this spring/summer. The O’Reilly Workshop: Build, Compile, and Run Your iPhone App in 2 Days will be helmed by iPhone app programmer Joe Heck, and is aimed at helping both experienced and novice programmers get up to speed on the basics of iPhone development, including the Cocoa programming environment, the Xcode suite of tools,…