Breast is best. Of course, I'm one of those weirdo-crunchy-granola-moms... I breastfed my kids until they weaned, the shortest time was 3 years, the longest was almost 6 years-old.
If your wife needs tips on pumping, or needs back-up info for getting breaks in order to pump (it's the law in the USA), then have her PM me.
If you *must* go to formula, try soy first. It stinks to high heaven but can help to keep your child from developing a milk allergy. Milk, nuts, strawberries, other allergens should be avoided until 12 months... In fact I exclusively breastfed all of my kids for at least 12 months because I am allergic to a ton of foods. If you wait to feed solids until after 12 months, then they are highly unlikely to get any food allergies.
Again, I suggest trying to figure out how to pump first, but as a last resort that's what formula is available for.