Not sure if you'd categorize these as garage, but the DIY series put out by Rhino Records a few years ago is superb. I have almost all of the punk ones, which are organized by city: Boston, L.A, New York. Then there are two volumes of U.K. Punk. The period covered by all of these is c. 1975-1979. Then there's a DIY series categorized as "Power Pop" which covers music from the early 1970s to the 1980s. Not sure if this fits the bill, but definitely worth a check out.