Llewella

Pronounced /ɬɛu̯ˈwɛ.ɬa/
Please note this is the Welsh IPA pronunciation and won't sound accurate in an English IPA reader. Welsh Ll's are hard to explain to non-Welsh speakers, but think of Sid the Sloth's lisp (yes, the sloth from the Ice Age films). The way he says his S's is pretty much the sound of the Welsh Ll. It is not said the same way as typical English S's, nor is it Fl, Hl, Cl, or a typical L sound.
Stress is always on the penultimate (second to last) syllable in Welsh names, so this is Llew-ELL-ah.
Source: I am Welsh.

Looks like it's pronounced Loo-ella.

I'm no expert, but I'm pretty sure ll's in Welsh are pronounced as S, so Llewella is pronounced -Shu-el-lə-

(CLU-ell-a) is the pronunciation, I believe.