Ok, well this calculator I was pointed to gives a lot of help:-
http://alex.phred.org/stemchart/Default.aspx
key in the parameters of existing setup under red and new possibilities under blue, it will then show what difference each stem would make. The spacers bit is easy to work out, the stem angle does matter and you may need to look it up, for example, with a 73 deg head tube angle:-
existing - reach 100, angle 10, spacers 60
new - reach 130, angle 40, spacers 60
the change of stem will raise the bars by 64mm and bring them closer by 18mm. I used that as an example as 130 long and 40/5 deg rise are about as long as you can do stemwise. Whereas if you were just going for bringing them nearer then a 70mm 40 deg rise stem would only raise them by 13mm but would bring them in by 51mm. I've found it really useful to plug in various configurations on this site, sort of a try before you buy type thing
If the amount of steerer tube you have available isn't enough, combined with stems, to bring the bars high enough, then you can use one of these:-
http://www.sjscycles.co.uk/product-...Raiser-for-1-1-8-Inch-to-1-1-8-Inch-16189.htm
This effectively extends your steerer tube and gives you a lot more options. But personally I'd look at different bars before that, have a look in my albums to see pictures of alternate bar setups. I assume it's currently a flatbar setup so you need to make sure the bar diameters are 22.2mm to match the controls. You also need to make sure that the clamp area on the bars matches the stem clamp. Looking at the Trek 7.1 the bar clamp will be either 25.4mm or 31.8mm(aka oversize or the alleged new standard). The rise on the bars will be about 30mm compared to about 90mm you could get on some North Road style. I have experimented with butterflies, north roads and midge (wide, flared off road bars). No doubt I'll end up with several sets of bars going spare when I'm finished. right now I've got one set of these North Roads spare:-
http://www.theoldbicycleshowroom.co.uk/alloy-north-road-handlebars-422-p.asp
They are a 25.4mm bar clamp and accept MTB controls and grips on the sides. Only problem might be the height, existing cable runs may be too short and need sorting. Anyway if they would fit, and you'd like to try them then I can let you borrow them on sale or return. PM me your details, if interested, I'll send them and it'll be £15 if you want to keep them, or you send them back....can't say fairer than that. I also have one adjustable stem, 120mm, up to plus 30 degrees going, the Ritchey one, say £15 again, looks like the link below but definitely the 25.4mm clamp and 1 1/8 steerer.
http://www.chainreactioncycles.com/Models.aspx?ModelID=39260