I was wondering could anybody point me in the direction of a good online service that prints minifig decals? I have no problem creating the designs etc but getting somewhere to print them is very hard. I would be happy to have a full custom minifig made if anybody could recommend a service.
You might try and post a request on the ALPS Decal Yahoo group. This is an e-mail group that discusses making water slide decals using the ALPS printer. There are members of the group that do have businesses that produce decals. I don't know how much people charge for custom decal sheets. You'll have to ask.
Most decals that these folks produce use multiple layers of white ink under your actual artwork so that it allows the decal to be placed on a colored brick (not just white). Your artwork also needs to be constructed using multiple layers that are lined up (registered). Because the layers are usually printed in the "spot" printing mode, the actual layer art is black. Think of each layer as a "mask". When they print it, they tell the printer that where ever it sees black, to print say yellow. Yellow is the "spot" color for this layer. You start by printing usually 2 white layers, then spot yellow, cyan, magenta and finally black. The unique feature of the ALPS printer is the capability of printing in overlay mode. What this means is that you tell the printer to print a layer, but don't eject the paper. The printer will rewind the paper back to the beginning and await your next print request. Each print request is a separate layer printed on top of the previous layer(s). This way, the final image is built up layer by layer. On the last print (usually black), you tell it NOT to do overlay and when the layer is finished printing, the printer will eject the paper. This type of printing is a lot of work and can use a lot of ink, especially white ink, which is expensive, but it gives the best results for the average hobbyist.
Like Joshua above noted, you can produce your own decals with a color laser (or inkjet) printer quite easily. You are stuck with a big cutting job if you want to put the decal unto a colored minifig body (using white decal paper). You can use clear decal paper if the artwork is black, because the decal shows fine on white, yellow, tan, red, green, orange, and blue parts. Remember, if you are using inkjet decal paper, you must coat the decal with a clear finish (Krylon), prior to placing in water (to remove the backing) when applying to your minifig, otherwise, your artwork will smudge and wash off your decal.