The most exposed bees are solitary bees and bumble bees, even though the issues with honey bees seems to be written about more in the press.
It is relatively easy as an individual to give the bees a helping hand. One can buy or build a so called bee hotel [1]. It helps the bees with nesting site locations. When sited it requires essentially zero effort but supports the bees and other insects.
One can also become a honey bee keeper, but it requires more effort. It is quite fascinating though. You can read about our efforts. [2]
[1] http://www.arkinspace.com/2012/06/welcome-to-bee-hotel.html