My images for my items are in varying heights and I would like to keep them that way. I would like to have them all aligned by the bottom of the images. Any suggestions?

Here is a link to the page:http://coastald.com/leister/automatic-welders

You could add a min-height to your image container according to the image that has the larger height.
Add in your template's css file
.catItemImageBlock {min-height:YOUR_HEIGHT_IN_PIXELS;}

Great, that seems to work, but I would also like to align the bottom of the images.

One way would be the following:
Add a .catItemImageBlock {position:relative;}
and div.catItemHeader span.catItemImage img {position:absolute;bottom:0;left:75px;}