Joseph,
I'm doing the inspection on steel pile splices for a new school this summer. The basics of the welding procedures the contractor is using call for SMAW, 6010 root and 7018 fill & cap. Some welds are made on roller racks with the pipe in the horz. position, these joints are single V with a 60* groove angle. Splices made in the upright position use a single bevel joint with a 50* groove/bevel angle. No backing ring on either.
The bottom plates have a rock shoe with gussets and a dowell. (the soil is rocky) They were installed on 10' sections by others so I don't have any details. I'm guessing they are 3/4" or 1" plates.
One of the references in our specs is Rautaruukki/Metform. This link will take you to their web page, brochures and publications section. Scroll down to "steel piles" and check out the first two choices. These are pdf files. They have weld procedures (with drawings), inspection procedures etc. and good photographs as well. These publications should give you plenty of information.
http://www.rautaruukki.com/rr_web/rr_icc.nsf/Documents/D1DB37822F16CF18C2256B840039ABA2?openDocument&lang=1: