I am currently breast feeding, I want to have 2 or 3 beers, how long does it take for alcohol to disappear from milk till next nursing?

Difficult issue. The alcohol actually transfers into breast milk as it is made and does not necessarily disappear before consumption.The rule of 1 hour/drink has been offered as enough to diminish transfer. Alcohol in any form decreases prolactin production and this can drop milk supply. It can sedate baby and will alter the taste of the milk. See: hale, t "medications and mothers milk" 15ed, 2012.
Breast feeding. In the days before law suits, beer was recommended to women who were breast feeding in order to stmulate their milk production.