A metal welding table is a great first project since wooden surfaces are a real fire hazard for welders, and it's wise to have a metal table to work on. Additionally, steel tables can accommodate a welder's clamp, and can be custom built to the welder's height for easy work on small projects. A steel tube is a great addition to hold the welding gun in a handy location.
Another simple project is a stand for a swedge or swage block. A good stand can provide a safe and convenient support for the block while the block is used for bending, dishing or riveting. Use schedule 80 pipe at an eight degree angle with shelves made of metal in the correct size for the swedge block.
This project can be as simple or complex as a user would like to make it. Bookends can be made from standard flat iron, or they could be created from horseshoes or other found metals. The simple L-shaped design requires few welds and can be adjusted until it's just right.
A rod storage container is a useful and simple project. Spare welding rods from the end of a box tend to float around the shop, being moved from one place to the next. Create a storage box for them by finding the largest piece of box iron available and cut it to a length that allows easy access to the rods but still keeps them upright. Weld the box to a wide piece of flat iron that will hold it upright.