I have walkin-in shower and planning on replacing it with a ceramic tile shower. What type of shower pan and connections I need, and step by step instructions.

You can build a mud pan by following these steps How to Build a Shower Pan (http://hoagy.org/house/HowToBuildShowerPan.html) However there are other options a bit easier for DIYer. Tile Shower - Schluter-Systems (http://www.schluter.com/4625.aspx) Tell us more about what you have now, maybe a picture will help us.