Okay, I am going to give this a shot, hopefully someone uses this, and this is not just wasted information! If you decide to try this, please let me know.
You can only use this method with any coin that was made from 1989 and below with a mint mark.
What I am going to teach you, you must have a photo editor that can produce straight lines. I use Paint for windows. If you cant find paint, then search it in the windows search bar at the bottom.
Reasons why this is a good thing to learn.
In my experience I have had a lot of unanswered questions, that I probably could have answered myself had I known about how to do this. There are a lot of times where people see one thing, and you see something different than them. Using this location graph, This will not only help you attribute things without having to send them in, and pay money, or wait for answers that you aren't going to get plainly because they cant tell, or there are too many RPMS/doubled dies to look at. But you can also use this to attribute Doubled dies, BIES,
Cuds, and other varieties.
For example. I will take you to the most recent post that someone by the name of Bates had a question about.
Lets just say this is your coin in the picture below.

As you can see, this is an RPM. Alright so you go to variety vista and look at all the rpms (there are 113 RPMS listed for the year 1960 Denver) It is also a large date (every large date has LG at the beginning of the title, so that narrows it down to 99 rpms that you have to look at, SD will be small date) Find the closest ones that you think is your RPM on variety vista/coppercoins/doubleddie.com
Save that picture to a folder that you can find easily.
First, you go to paint. Now when you are in paint, you want to load the picture, to do that, follow these steps.
At the top left hand corner, you will see a clip board with "Paste" written on it. Click the small arrow that points down on the clipboard. (Click Paste from, in the drop down menu) Find the picture that you took from variety vista.
I chose LG 1960 D RPM- 068 because it looked very similar( You need to pay very close attention to detail) Also RPM 38 looks similar too. But later I will show you why it is not RPM 38.

After you loaded that picture, you will see a box up top in the middle called "shapes", in the box you will see a straight line, click that.
Then, use all of the mint marks straight lines, and insert lines to make a graph.
Like this.

See how I used the mint marks features to determine the exact location of the mint mark?
Okay after you get that done, save it.
Then you create a new file by clicking File (left hand corner)
Then use the clipboard again, click the arrow, now click the picture of your cent in question and do the same thing.
should have something like this.

Okay now, we put them side by side to compare!


As you can see the shape of the graphing is very very similar to each other.
Okay, Just so you know that I am not just lying about this, I will show you why this is not RPM 38
Check out the side by side comparison with your cent and RPM 38, they do not match as you can see by the shapes of the connecting lines.
First picture below, is RPM 38 taken from variety vista. Second picture is your coin in question.


Yes, it is rather a lot of work for you to do, but once you get the hang of it, you can do it without thinking. If I can teach myself this, I am confident that you will learn faster then me cause I am a slow learner. Beats having to pay for attribution, beats not getting an answer.
Here is some tips I have for you on paint!
If you need to undo, At the very left hand corner there is two blue arrows pointing left and right. That is the undo button.
Also, after you paste your picture to paint, the corner of your picture, you can click that and hold while dragging it, to resize the picture. Variety vistas pictures always seem small on paint, so I always have to resize it.
Here is the Post that I was talking about. As you can see, no one wanted to touch the attribution part, and just said "YES its an RPM. instead of telling you what one, as the question was.
As you can see, this method gives you the answer.
http://goccf.com/t/322475 Anyways, this took me a lot of time to explain, I really would appreciate if you tell me that you used this because of this teaching! If you have any questions, comments, or if you want to give me a pointer/advice on how to use paint better, let me know!! I will also make a youtube video very soon to walk you through it if this kind of overwhelms you! I know it would overwhelm me! It really isn't that complicated though, I think a little kid could figure out how to do this without even me teaching them.
But let me know if this is confusing, I will try to make that video for you soon and send it directly too you when I get it finished.