It has taken me years of doing and undoing to get everything where I can lay hands on anything I need and I still find myself confused and digging.
I have found that in the beginning I was dealing with a lot less and it was so much easier. My original plan was to keep everything on index cards in a small file box. I had tabs that included each piece broken down in expenses, dimensions, problems, patrons and shipping. Then I had my tab for services I use full of business cards.
I quickly out grew the file box and began saving all information on disc (but I also printed out a paper copy for quick references). Therefore my file box became a standing five drawer metal file.
I also learned to deal with financial record keeping, what to save and what is needed to back up your business. Considering the number of years you must keep information it is often overwhelming if not organized.
My photography (both my research pictures and my body of work) began to get out of control. In the beginning I was required to send only slides as entries to shows or studios portfolios. Eventually everything went to digital and even sending your art work entries was done online.
Another lesson I am learning is that the stark white background with no shadows required by most juried shows years ago are not acceptable photography for online. So therefore begins another lesson in redoing all sculpture shots.
My personal suggestion to all beginning sculptors, take your own photos and get the equipment in the beginning that is necessary to take excellent pictures, even take a class. It will benefit you and that will be one more of the facets of sculpture that you won't be paying someone that does not care about your work to do.
(Little suggestion, even taking your own pictures during clay work will show you errors sooner than just looking at the work...photo's jump out at you).
My research is busting at the seams in a multi-fold file but this is something that you can not do without and you constantly add to it.
Your body of work photos are more important (for your portfolio or as handouts in the form of postcards or yearly mailings. They have to be kept gently, flat, accessible and ready to grab for a show. Make sure they are stamped on the back side with all contract information. You are right in thinking that it is a given that some people just like to go to shows and collect pictures and that is a waste but you never really know when a real patron that is interested but doesn't want to approach you until later may be taking a picture to remind them of your lovely work.