Hello Dreedo,
You definitely have AMOS The Creator. Do you have a manual for it also?
The best option for you to build sprites is to locate your DPaint disks and design them in there. Then save the image to the disk, load AMOS, and use the Load Iff command to open the image. Then you'll need to use the Get Sprite or Get Bob commands to extract the sprite image from the picture you loaded and put it in the sprite memory bank. The Sprite bank is normally bank number 1. You can view all the current banks by going to Direct Mode (type the escape key from the editor) and typing "listbank". This will show you all the memory banks, their number and type.
Once you've grabbed all your sprites and put them into the sprite bank, you can then save the bank to disk using the Save command. Like:
Save "mySprites.abk", 1
Which will save memory bank 1 to the disk as mySprites.abk.
Then, the next time you want to load your sprites you can just use the Load command:
Load "mySprites.abk"
That way you won't have to re-grab all the sprites each time you want to use them.
On a separate note, what kind of Amiga are you using to run AMOS? A500?
There are always ways to get data from the Internet to your Amiga. :-) The problem is that sometimes it just requires a little time or money. For instance, you could hook up a null modem cable between your Amiga and a PC and transfer files over it using a terminal program. That's a bit advanced, but I've done it before. Alternatively, if you have OS 2.x or greater you could use CrossDOS to read a 720k DOS disk on your Amiga. You could then save the .adf files for AMOS Pro to a DOS disk (it may require using a packer like lha or zip in order to fit on the smaller DOS disk) and then read the DOS disk on the Amiga, unpacking the .adf file and using a tool like adf2disk to copy the image to a real disk. And the other option is to ask someone else to copy the disk images and send them to you.
Hopefully some of this will help you out.