ordering prints..

[littleny]

im wondering about ordering prints (most likely 8 x 10's) from cropped images...
how does this work out? how can i be sure from image information in photoshop that my images after they've been cropped are suitable for print sizes i want to order?

also if i crop to an irregular size will a place like mpix print an irregular sized print? and will it cost me more?

i've been trying to understand how this works and really dont understand.

[LindaOH]

When ordering from snapfish, there is a caution icon that appears if the image is not suitable for the size of print.

To overcome the irregular size issue, I add some white to bring it to a regular size and cut it off when I get it. Example: If you have an image that would be 6x10, add two inces of white to make it an 8x10, order an 8x10, and then cut it back down to a 6x10.
Does that make sense?