Affiliate Marketing Secrets

im building a website what will use affiliates, can i use companys logos etc ie samsung, sony etc on my site??
ill need to use these for the brands of the products of the affiliates

im creating a site what will use affiliates, im going to need images for my catagories and brands list, can i get these off google or get the images and brands pictures of some of the sites im going to advertise on my site via a affiliate program
thanks