Today while scavenging through bulk pick up piles I came across a box of vinyl mostly classic rock stuff. I am probably going to selll them at the flea market but was wondering if there is some way to tell if they are reprints or from when they came out. Any web site link that is understandable by a non expert would be helpfull
Wow, nice find, but what you are asking is very complicated. The ways in which LP manufacturers identified their products varies a great deal.
There are often entire sites with fan forums dedicated to figuring out just ONE popular artist's work. Once you get past the numbers on the label it really gets dicey, most of the time. If you mean, by the use of the word "re-print" that you would like to know if the LPs were higher quality like those from major labels, you can often get clues by finding that an Atlantic (for instance) LP was not manufactured by an Atlantic affiliate. That is a certain give-away that it is most likely a re-issue.
The thing to remember is that each time the next record is "pressed" it wears out the master a slight bit. So, if possible, a collector would prefer to own an LP made during the early life of a master disk. Some masters are also more detailed or "true to life" than others and therefore more desirable. Not only do they wear out over time from use, some masters are lower quality from the beginning also.
In the deadwax (that area after all the music on an LP side, towards the innermost grooves, at the center) there are sometimes clues engraved into the various masters that were used to help identify which vinyl LP was produced by which master, but there is no standard way to enter this information and it was often neglected. People always got creative with that part, too. I have often used google to search what I find in the deadwax, but not all of the inscriptions are categorized and identified.
There is also information (sometimes) at publishing and record companies' websites which helps.
Honestly, it's not a reasonable pursuit for an amateur interest. Once you define the LP by the numbers printed on the label (re-issues often have a different number from the original or in some cases, it is the same, but a series number follows the set of numbers which identifies the group and album) and the "type" of label, stop there. This is basically what I do, because it is so involved researching a run of LPs.
The only ones that I own that I truly know the whole scoop about are the ones that I bought myself out of the first run of pressings at the time of release. Most of the other LPs I own, I only know details because I got lucky in my research or the lives of the masters were well documented, as in the case of Beatle albums.