"
I: initially before another vowel has the consonantal sound of y in you, yore in Sindarin only: as in Ioreth, Iarwain. See Y." -- Appendix E
"In Quenya ui, oi, ai and iu, eu, au are diphthongs (that is, pronounced in one syllable). All other pairs of vowels are dis-syllabic. This is often indicated by writing ėa, ėo, oė.
In Sindarin the diphthongs are written ae, oi, ei, oe, ui, and au. Other combinations are not diphthongs." -- ibid.
"Where the last syllable but one contains (as often) a short vowel followed by only one (or no) consonant, the stress falls on the syllable before it, the third from the end." -- ibid.
Therefore: /'i: orež/ (preferrably with the Elven [R])
See the excellent online resource pages
The Pronunciation of Old English and
The Historical Grammar of the Old English Language for all guides on the names of the Rohirrim and Men of the vales of the Anduin such as the Beornings.
[ August 12, 2002: Message edited by: Sharku ]