As promised - a list of custom earplugs:
I have these. They are the best thing I've ever bought outside of my guitars (my MONO cases are a very close second). I don't know how I survived without these. I go to a lot of shows, play a lot of shows, rehearse a lot - I'm around loud music a lot. These are infinitely beneficial for me. I look forward to retaining most of my hearing for my life thanks to these (and Eddy McGrath).
I have the 15dB filters, in case you're wondering.
Northeastern University in Boston can make these for you. They're worth every penny. You get a hearing test first and then they make the molds. It takes about three weeks to get them.
Westone - My friends in Filligar have these for their in-ear monitors.
They're all really a variation on a theme. If you want in-ear monitors, then I'd look into Westone. I recommend something - I highly highly HIGHLY recommend doing something to preserve your hearing IMMEDIATELY. Once it's gone, it's gone.