After narrowing it down to Township, Range and Section, (try to get itdown to the 1/4 section if you are just in one or however many you are in, and you have checked LR2000, (which will only break out to 1/4 section), check with the mineral dept at the BLM state office. They will break it all the way out for you, usually over the phone. They can also tell you if the gov't holds the mineral rights ( Gov't has to hold mineral rights to be able to file a claim). If all good so far, check with the county recorder. They have the CURRENT status of any claims and are the LEGAL word on claims. BLM will gladly take your $$, and tell you it is a civil matter for the courts if you overfile on a current claim.
If still all good, get the current forms to file, usually can find at a good sized stationary store or office supply house, fill out and take to county and record. Then send to the BLM state office with the appropiate fees for the size of the claim. They will process and send back. Need to file an intent to hold by August 31 every year, and your assesment filing by December 31 each year. On the assesment you can either do $100 worth of work on the claim or pay the acreage fees. You can file both in August and save worrying about forgetting the December date. Always send all paperwork to BLM via certified return reciept just as a precaution. Covers yourself if they try to say they never got it.
You need to have one name for every 20 acres or portion there of, ie. 40 acres(2 names), 60 acres(3 names), up to 160 acres(8 names), the maximum size allowed for a placer claim. You will probably need to post a location notice, and mark the corners of the claim.
Once you have a filed claim, then you can talk to GPAA and Kevin about listing it for GPAA member use.
Good Luck, hope it works out for you.