Hi Tom, you're very welcome.
For the new material, I track the announcements Elusive Disc and Acoustic Sounds of coming releases. Between them one will see pretty much any of the newly pressed vinyl.
For previously released material from used LPs, there are several regular sellers on eBay who regularly carry the kind of material in which you're interested, and their stock typically sells at reasonable prices. I can give you some names if you want to send me an email.
Also, there are several sellers with monthly lists of "set price" LPs. Two monthly list sellers from whom I've bought records for years are:
Ars Nova (Paul Hartin) and
Mikrokosmos (Peter Fulop). Both publish a new list as of the first of each month and I highly recommend them both.
Kind regards,