Do you mean investing as in monetarily for future gain or as in "I hope this record is worth the $ and time I spent on it?"
That said, many artists still release their latest works on vinyl, but the vinyl might cost as much as or more than a CD version. Any quality independent music store in your area should carry some vinyl inventory.
If you don't want to spend that much on new records, then check out your area thrift stores. They'll usually sell their records for $1 (US) or less. You can usually find quality classical recordings or something that will pique your interest. I'd avoid the Rick Springfield records unless you're really into him. I recently picked up Walter Murphy's "A Fifth of Beethoven" and a nice Bartok album this way. Be sure to check the condition of the record before you buy it.
If you're into or curious about Jazz, then try finding Len Lyons' book The 101 Best Jazz Albums (ISBN 0-688-03720-8. 0-688-03720-5 for paperback). Published in 1980, it's somewhat dated, but he covers the history of Jazz quite well and gives his selections for the best records of each stylistic period. He also lists other quality/noteworthy albums at the end of each chapter. Or, just buy something by Miles Davis from the 50s, 60s, or 70s (at least two records from each decade would be best).
Finally, check out your local used record store. Most college towns will have at least one. While the prices are higher ($4-$8 or so), the selection will be much better than the thrift stores, and you can find better variety and quality.
If you liked the Beatles records, then look for XTC's Drums and Wires or Black Sea. If you want something more rockish or bluesier, then try some ROLLING STONES with Beggar's Banquet or Let It Bleed. LED ZEPPELIN'S II and Houses of the Holy are quite good. If you want something more Progressive, then try any of the early stuff by YES, GENESIS, PINK FLOYD, or KING CRIMSON.
If you haven't heard them, then ELVIS COSTELLO's This Year's Model and Armed Forces are revelatory recordings and excellent examples of early Post-Punk sensibility. Not knowing what you really like or already own, these are just a few of my suggestions. As always, if you see something that looks interesting and fits your budget, then try it.
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