I have recently been made aware of online drag/drop collages. I got this collage from Scrapbooks Etc. They have some great tutorials and a wonderful message board for additional questions.
Here is how I was able to create my own collage using PSE 4.0
Open the template in PSE (or other photo editing software)
Open your chosen pictures
Click on the arrow with the plus sign
Choose Layer; Group With Previous
This will put your picture "inside" the template as such:
Now, you need to resize your picture so it fits nicely within the template.
You will hold down your SHIFT key on your keyboard; place your mouse arrow over a corner of the picture; left click. Hold down both shift AND left clicker as you drag the mouse until your picture is the size you want.
To move the picture within teh template, place your arrow over the center dot of the picture; left click and drag until the picture is properly placed.
Now you can click on the little green arrow to accept
Now go to the left and choose the Marquee tool
Create a box around the part of the picture you want to remove
Click DELETE on your keyboard. This will remove any part of that picture that is within the marquee square.
Continue this process until all your pictures are placed and sized as you like.
When you are finished, click on Layer; Flatten Image. This will group everything together so it is just one single picture. Make sure everything is as you like it.
You can now save your file. Go to File; Save As.
Choose the folder in which you want to save this picture.
Make sure you rename your file as you want.
Don't forget to change your file format to .JPEG
And, there you go! Your completed collage!
Now, you can print this out as you would with all your other pictures. You can send this off to online printing service (Target, WalMart, CVS, Kodak, etc) and choose the size you like. You can print at home too using photo paper and choosing a size that is no bigger than 7.5x11
I hope this helps you do more with your digital programs and photo editing software!