i havnt got stamina in my build - but you will need an End reduct in each of the toggles and 1 in each of the powers to make it viable in my experience.
You can quite happily get away without stamina (I have at least), I would however suggest having an end reduction on each of your toggle powers and on your most used non-AS attacks. Remember that not having stamina you'll always have to be very careful if you get into a protracted fight. Apart from that there isn't a big problem not having it.
[Edit] It seems Mr Whiplash got there first whilst I was typing 
My stalker doesn't have stamina at level 26.
Up until recently he functioned quite well, although he'd usually have the least endurance of the team. Depending on the team make up he might or might not have to stop for a breather.
Then I forgot to turn my defensive toggles on for about half an evenings play and didn't really notice the difference other than my endurance useage was much better.
Moral of the story: if you manage your toggles you can survive perfectly well without stamina (certainly up to l26).
However, I'm probably going to pick it up in the near future because:
- I use teleport as my travel power
- I wanted swift so I don't need to use sprint so often
- I wanted health to give me a little more survivability when I have to scrap.
Thanks for the help. 
im lvl 21 and i find the heal move helpful but i really need endrance i sugest getting stamina at lvl 22
zomg stam FTW
mind u i got ninja blade/regen so stam helps loads for the end drain situation whilst fighting
I've never played a Stalker and have though about rolling one out. Also I have no experience using Martial Arts.
Using Villain Builder I've come up with a build which is very tight so I've left off Stamina til later on...
I thought with the low end cost of my toggles I might be able to get away with it.
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Exported from Ver: 1.6.8.0 of the CoH_CoV Character Builder - (http://home.comcast.net/~SherkSilver/index.html)
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Name: STALK
Level: 41
Archetype: Stalker
Primary: Martial Arts
Secondary: Ninjitsu
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01) --> Thunder Kick==> Acc(1) Dmg(3) Dmg(3) Dmg(5)
01) --> Hide==> DefBuf(1) DefBuf(37) DefBuf(37)
02) --> Ninja Reflexes==> DefBuf(2) DefBuf(5) DefBuf(36)
04) --> Danger Sense==> DefBuf(4) DefBuf(34) DefBuf(34)
06) --> Assassin's Blow==> Acc(6) Acc(7) Dmg(7) Dmg(9) Dmg(9) Rechg(11)
08) --> Hasten==> Rechg(8) Rechg(11) Rechg(17)
10) --> Focus Chi==> Rechg(10) Rechg(13) Rechg(15)
12) --> Placate==> Rechg(12) Rechg(13) Rechg(15)
14) --> Super Speed==> Run(14)
16) --> Kuji-In Rin==> Rechg(16) Rechg(17) Rechg(19)
18) --> Cobra Strike==> Acc(18) Dmg(19) Dmg(21) Dmg(21)
20) --> Kuji-In Sha==> Rechg(20) Rechg(23) Rechg(23) Heal(25) Heal(25) Heal(27)
22) --> Stealth==> EndRdx(22)
24) --> Hurdle==> Jump(24)
26) --> Crane Kick==> Acc(26) Dmg(27) Dmg(31) Dmg(33)
28) --> Smoke Flash==> Acc(28) Acc(29) Rechg(29) Rechg(31) Rechg(31)
30) --> Health==> Heal(30) Heal(37) Heal(39)
32) --> Eagle's Claw==> Acc(32) Dmg(33) Dmg(33) Dmg(34)
35) --> Stamina==> EndRec(35) EndRec(36) EndRec(36)
38) --> Kuji-In Retsu==> Rechg(38) Rechg(39) Rechg(39) DefBuf(40) DefBuf(40) DefBuf(40)
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01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Assassination==> Empty(1)
02) --> Rest==> Empty(2)
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