The ACM Digital Library offers unlimited access to 1. ACM Digital Library Core Package of magazines and journals with archive to the 1950s. 2. ACM Digital Master SIG Package of newsletters and 85 conference proceedings with available archive. 3. The Online Guide to Computing Literature, ACM's citations database that expands users' searches to include over 750,000 non-ACM works in computing and IT from over 3000 publishers.
Source List: Sources can be browsed while online.
Association for Computing Machinery Digital Library