Fonts
If you google web safe html fonts you will get a list of the possible fonts that you can use on your web pages.
Any different fonts you will have to create an image to include (you can see all the fonts installed on your machine, but there is a chance that the end user wont have the same font on their PC eg earlier windows version/mac user.. you will always see the same images)
Once again, google royalty free fonts or something similar to find a plethora of sites with font types you can install to windows for use in your favorite graphics package. Just make sure you read any T&C's on the sites you visit concerning the fonts.
Images
Generally if you see an image on a website and the site it has a copyright notice, you cant use the image without permission.
Once again, google "royalty free images", should throw up a list of sites where the images are completely free to use under different conditions. Make sure you read the terms and conditions for each site/image you visit and use as the conditions for using the images can vary somewhat.
Some terms and conditions (T&C's) you may come across:
One-off fee to use
Completely free to use (commercial and non-commerical)
Free use on non-commercial websites (commercial requires permission/fee)
Free to use but require a link back or credit to images owner
When in doubt about anything, contact the creator/originator of what you wish to use on your site (if you can), most will gladly give permission if you take the time to approach them with a friendly and well written email.