Question
Where can I get Ericoid mycorrhizae and how can you treat establish plants....blueberries,azaleas,etc.?

Answer
Ericoid mycorrhiza are a symbiotic relationship between fungi and the roots of plants from the order Ericales. Ericoid mycorrhiza are considered crucial for the success of the family Ericaceae in variety of edaphically stressful environments worldwide (Read, 1992).

Ericaceous plants commonly co-occur in soils with leguminous or carnivorous plants (Read, 1996), further highlighting the low nutrient status of these soils. Ericoid mycorrhizal fungi, which are predominately ascomycetes, enable their host plant to obtain nutrients in these depauperate soils.

You can buy some here:  http://www.greners.com/i/nutrients-additives/base-additives/mycorrhizae.html.  

Blueberries also need to grow in acidic soil... 4.5 pH is suitable. Here is a site with lots of information: http://www.extension.umn.edu/distribution/horticulture/dg3463.html