Start with a few good books on LF photography. A forum with much valuable information exclusively on LF is http://www.largeformatphotography.info/forum/http://www.largeformatphotography.info/forum/. People have been using LF equipment for a long time, so there is a wealth of cameras and lenses, new and old, available online and sometimes in stores and other venues. Since great photos were made long ago, old gear in good condition is still practical. 4x5 film has the advantage of better digitalizing on mid-range flatbed scanners than does medium format.
LF cameras are usually used on tripods. Don't skimp here. While cameras often come and go, a good tripod should last a lifetime. New tripods are not necessarily better than old ones; just more expensive. I have several types and sizes of tripods, but most often use two ancient Tiltalls.
A large format press camera is closer to what you have used than the more versatile field or monorail view cameras. Field cameras are more transportable than monorail. For studio work, the monorail is often preferred. Which type of camera should be determined by your subjects and style of shooting.
Knowledge is power. Books are a great source of knowledge, but the internet can be even better. Feel free to ask any question here and on other sites. We all had to begin LF photography sometime.
edit -- Rick thinks and types faster than I can!