Hi,
I’m working on a multiplayer fps game and so far I have been using placeholder animations for my characters.
Its time to replace them with real animations and I need help.
Can someone please show me a good sideview of a walk and run cycle. I have seen many tutorials but the problem is that most of them cover cartoon characters and I need to animate humans.
Your best option is to just do a quick google search for some images of walk/run cycles.
Heres what i found after 2 min on google, not sure if stills are as usefull as animations… but they should still be helpfull 
Theres hundreds more references online, you just have to dig a little 
Those “stills” are some of the best and most respected studies of human motion ever made, by Eadweard Muybridge. They were made before motion picture cameras were invented, and cover a vast number of naturalistic motions, human and animal. They are valuable as anatomy refs as well. Collect them all!
@chipmaque - Thankyou! That name rang a bell with me… and i just remembered it was on that program called QI, they made reference to his book named “animal locomotion” 
Thanks for reminding me of his name and providing the link, a goldmine of resources for sure!
Quite welcome, Jamie. I’ve studied human figurative art for many decades, since long before digital media existed, and it’s SO cool to have so much of that kind of ref material available now. Way back then you had to dig it out of libraries and bookstores, if you could find any of it at all. I’m very pleased to pass it on, so to speak.
this is the best place i have found for works and research by muybridge -
http://www.eadweardmuybridge.co.uk/
You will probably be most interested in these sections 
- http://www.eadweardmuybridge.co.uk/muybridge_image_and_context/human_figure_in_motion/http://www.eadweardmuybridge.co.uk/collection_map_and_database/
Actually, this seems to have many more links to his work, with many more photograph resources
They are definatley going in my bookmarks, as the OP has already stated, it is hard to find good references relating to human motion
http://www.artcyclopedia.com/artists/muybridge_eadweard.html