Just some basic things, I see people charging credits/money for something that takes less than a minute.
Firstly download this (photoshop cs6): http://portableapptrash.blogspot.sg/[/CENTER]
It's got no virus's, it's only 90mb's, you don't even need to install it.
If you wan't to make a circle avatar without or without border:
Step 1: Dimensions
I personally use 400x400 (pixels not cms/inches) as it re sizes quite nicely.
Step 2: Find the Image you want to use and resize it to fit, using ctrl + t.
Hold shift to keep the picture from becoming distorted, move it around till your happy with the placement
If you need to zoom out, hold alt and scroll
Step 3: Selecting the Elliptical Selection tool
Hold down mouse one to bring up the selection menu
Step 4: Place your cursor in the middle of the image, click and drag outwards whilst holding shift + alt
Step 5: Press ctrl + x to cut the image out, press ctrl + v after you have done that
This separates the background and image you want to keep
Step 6: Hide the un-needed layers (Layers 1 and Background) by clicking the eye
Step 7: Re position your image to the center by using the move tool, you can click the tool or hit "v" on your keyboard
For small movement, use the arrow keys whilst you're on the move tool
Step 8 (If you want a border on the image): Right click the layer and select "Blending Options"
Step 9: Select Stroke and choose a color that you like
The size makes the border thicker, the opacity is how see through it is
Step 10: Save the file
File > Save as > .png
You can also save the photoshop file if you would like