I have thought about taking a Ipod along plug it in your amp with an adapter,and set my volume level and go back to the rear of the venue to see what the sound man has cooked up. It could have some steel playing on it.At least you could see if you were in the mix.
PLEASE DON´T!
Here´s why:
1: You can´t have an iPod play along with the band to see how you´re placed in the overall mix. Even assumed that your band could play along with it, it´ll never have the same volume as you, as your own picking will always change with the band´s energy.
2: The mix during soundcheck and later on at night will always be VERY different:
Empty places always sound much more reverberant and worse than crowded venues. A good soundman will adapt the mix differently in those two situations to suit the different acoustic requirements.
3: Concentrate on why YOU are there and you can do best: play steel guitar. Don´t distract your mind by doing another man´s job .
Being a professional sound engineer myself, I always stick to only playing when I gig myself.
I NEVER go out and listen, this is only getting on my own and the soundguy´s nerves...
Leave the sound job to the sound people!
You wouldn´t let them tell you what licks to play, either.
This is not meant in an offensive way, but please be cooperative and treat the guy as a member of the band.
4: Best in my opinion (from working on both sides of the faders) is a fairly close positioning of your amp with just as much volume to be real comfortable. Keep "acoustic pollution " on stage to a minimum.
5. Most important :
If you don´t trust your soundengineer, get (and pay) another one that you feel confident with.