My brief search into this only led to the ACM digital library, which seems pretty good. Are there any other services, free or paid, that provide access to old and new computer science research?
Library Genesis has scientific article search (and free and instant download). It finds almost everything I search for, even obscure papers from early 20th C or before.
http://gen.lib.rus.ec/
Also you can click on the journal titles and explore within each issue.