It's pretty much the opposite of what you might do on a PC where you would go to your email program, draft a message and attach the file. On the iPad you start with the file which is associated with an app. The app controls what you can do with the file...email it, print it, edit it, etc. For instance, if you want to email a photo go to the Photos app and open the photo. Touch the icon that has an arrow popping out and pointing to the right. You will get a list of the actions you can take. Select "email photo" and the iPad will open an email with your photo already attached for you to edit and send.
If you want to send more than one attachment at a time you will need an app like Goodreader that has some file management capabilities.
Photos and web clippings can be sent from the email app itself through the copy and paste method also.
The IPad Forum is a community of members from all walks of life and from all over the world coming together to share our experiences and to help each other learn about this wonderful piece of technology the Ipad. There is a wealth of information already here in the many threads we have so doing some searches will answer most of the questions you have. If then you cannot find the answer you are seeking then by all means post your question. There are many friendly and informed members here only too willing to help you.