I'm trying to wean my DD off forumla, she turned 1 at the start of the month. I found that cows milk gives her terrible wind and tummy aches so she's having lactose free cows milk at daycare and has been fine. I'm also going to try that at home and I will try some soy. I will try normal cows milk again in a few months time.
I find for myself that normal milk gives me bloating and terrible wind pain as well as making me rush to the loo straight after drinking it, so perhaps both DD and I have an intollerance to it, though I'm not yet going to say that DD is intollerant, I will try it a bit more. She doesn't react badly to yoghurt.

I would advise keeping a tin of forumla on hand while introducing milk just in case. We went from buying 4 tins a fortnight down to last fortnight only buying 2 tins for a whole fortnight. We are also decreasing the number of bottles DD has and offering solid food first. She's now having a bottle at about 7am (formula), then one at 12:30 (lactose free or a half/half mix of formula & lactose free) after she's had lunch, then she doesn't have another bottle until about 8pm (formula but will be trying lactose free milk as of this week) before bed. If she wakes in the middle of the night she'll have one then as well