blending

www.allegrakate.deviantart.com

i made a post yesterday about this collage, thanks for the help!
well, i tried to blend the images i had together, like above... but it didn't work. i tried blending them together with the eraser tool, my lecturer also taught me to blend images together this way, but i've forgotten how it goes.
could anyone post a quick tutorial on how to blend images together, like above, please? i'm fine with the brushes, i know how to do that, just making the images blend is what i'm struggling with!

are there any good tutorials that you used to help you blend?

mhm, also recommend me a good community/site for brushes!

i use photoshop 7.0

please and thank you, i would appreciate this alot.