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You will eventually not need the fingering chart at all. I’ve been playing since early January and I don’t use it at all now. You will learn where the notes are as you become more familiar with the instrument.
I would think that the way you hold the instrument is a matter of personal preference. The only problem that I could think of would be the tendency to drop the whistle when playing the C#, but if you keep your pinky down or cover the lowest hole on the C# then that wouldn’t be an issue… I tend to hold mine low too. I think it’s because I spent so much time playing it while I was looking down at the music…
cranberry, try something you know using only the printed music…try something else just off the top of your head…and try something you DON’T know just by listening to a very patient person.
You’ll find the way that’s best for you. But reading tab is SLOW. It really is best to get away from that as soon as you can.
some tunes to try without written music:
I’ve been working on the railroad
The Garden Song
Mari’s Wedding
My Grandfather’s Clock
If you’re heading for Irish music, there are loads of tutorials, but you really need to know what you’re trying to play, so you should get one with a CD.
My 2cents
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I think you’ll find that if you hold the whistle out, you can let the weight rest on your thumbs, allowing your other fingers to be more relaxed and light in their movements.
Jon Michaels
Tyghress is right… and this is exactly what she told me when I was having -so- many problems learning. Tab is really a crutch and it will keep you from learning. I -hated- to hear it, but I have improved more than I can explain since I let go of the fingering charts. 
What I did was well, first I went out and got a better whistle, but I dont think that is your problem 
It was a huge part of mine. The other was in getting frustrated because I could not understand sheet music. It might take a little while, but go on over to the whistle shop and read their tutorial for beginners. Learn what certain notes mean on the scale. One thing I did was I drew out a scale, and in quarter notes, I wrote out the scale in D, along with a small fingering chart at the bottom, although I dont even need it at this point.
Once I did that, I put it somewhere that I could see it, but not where it would be so in my face that I was relying on it. Anything I want to learn, I write out as their notes in ABC (though it isnt really the ABC everyone else seems to use) And I listen, listen, listen… and listen to whatever it is until I can hum the entire thing by heart. Most things I am learning now are tunes I grew up listening to in the first place. (MacPhearson’s Rant, Mairies/Mara’s wedding etc) I am guessing that eventually I wont even need to translate the notes out, and that I will be able to tackle a tune just from its sheet music, but in the meantime, this is working.
Try to learn things that are familiar to you, then tackle something completely new. And remember to take your time
Hi Cranberry (ex-Touw, I miss him, he rocked!),
The angle of the dangle does affect the sound, and your projection.
There’s a tendancy to look down, and hold the whistle almost straight down, if you’re reading off sheetmusic on yor lap or lying on a table. Put the music on a proper music stand, or better, discard it, and you can sit up straight (or stand) and get better projection, and airflow.
Like in singing, the air should be coming from ALL your lungs, not just the top third, and for this you should be breathing deeply & not restricted. Breathe from your diaphragm. Holding the whistle at a low angle is restricting your ribs & lungs. Try to aim for an angle of 70% to the vertical or 20% below horizontal.
As noted above, this allows your thumbs to take the weight of the whistle, not your lips, so you don’t need to worry about dropping the whistle. This should make you more relaxed all over, and especially in the hands & forearms.
Think of the flow or air being as unimpeded as possible, pushed from your diaphragm through your lungs, throat, and mouth, and out through the whistle. Try lip whistling with your chin on your chest, and then lifted high. Feel the difference?
For tunes, try some slow airs. Look up
The South Wind http://trillian.mit.edu/~jc/cgi/abc/findtune?P=south+wind&F2=find+(wide)&L=100
all beautiful airs, and not too tricky.
Good Whistling!
I was being taught by a piper and he always made us bottom d with just the 3 fingers for the top hand 3 fingers for the bottom
eg
xxx xxx
the for bottom e 3 fingers top hand 2 bottom
eg
xxx xxo
for the f# howerver it bacame 3 fingers top hand bottom hand index and little finger which now stayed on all the way up to 2nd octave d
eg
xxx xoo x
xxx ooo x
xxo ooo x
xoo ooo x
ooo ooo x
oxx xxx
ope this makes sense, and it means you can play at which ever angle you like.
learning to play “by ear” instead of by the written notes is the absolute best way for the whistle. It is effin’ frustrating a HELL at first, though, so be prepared to get your doc to double your Zoloft scrip.
… and then one day, you’re suddenly able to play…
… and, omg, it’s such a revelation!
serpent
P.S. Martin, Cranberry is female, lad! 
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Well, I’m only a snake when I want to be… or someone finds it exciting to play with me…
serpent