This is actually something that I have been thinking a lot about. I think it is wonderful that we have players out there who are willing to arrange and share tabs (particularly those that are from songs in the public domain)--and I also love Ian Chadwick's work to collect vintage uke music.
As a technology person (in addition to being a musician and music teacher), I have scanned a lot of music from various school libraries to use on my iPad as sheet music (once you eliminate paper, you don't want to go back). In the process, there are hundreds--if not thousands--of scores that are permanently out of print and of those, some that are in the public domain (some of these school libraries go back to the early 1900s). Quite honestly, if a song/arrangement isn't kept in the forefront, it is pretty much gone forever.
I know of a small music publisher of mainly Czech tunes where the owner/operator is in her 80s. When she leaves the business, that company folds along with all of its arrangements. I have encouraged that person to turn their entire library over to the CPDL when she retires, as no more income will be needed, and if not, all that music will be lost.
Anyway, while there is an IMSLP, CPDL, and PDF Music Library, wouldn't it be great if there was a non-profit central place for ukulele music and tablature? Copyright is a consideration, but for the Renaissance pieces mentioned above, that wouldn't be a problem unless Jamie didn't want them posted (in this case). I wonder how we could make that happen?
And I know there are ton of chord and tab sites...that isn't what I am talking about--but the material on those sites is also subject to the host and their continued maintenance (and payment) for those sites and URLs.