Ah - my screen name.
I'll tell you, I'm not 100% sure how to pronounce it. I took both words from the Hebrew Tree of Life. They are two of the names of God. Ahavah means 'Love' and Ehyeh means 'I Am'. I don't speak Hebrew, so I'm probably pronouncing it wrong.
But as for how I personally pronounce it - and I hope this makes sense - is like this:
Ehyeh: Ay (as in long 'A') - yuh