Welcome to LAF.

There's a sub-forum where new members may introduce themselves, find it
here.
Regarding your question on decals, both Warlord and Wargames Factory used to provide waterslide transfers in (most of) their plastic boxed sets. If that's no longer the case, have a look at their webshops, transfer sheets are around there. Designs are similar to the transfers offered by
Little Big Men Studios. LBM has a large collection of decals suited to specific ranges. However, these transfers are 'rubbed on', so you have to decide yourself which method you prefer and go from there.