Ne zaman geldim namaz kýlýyordun düþünyordum

My attempt when you came I thought you were praying. Pls correct thank you

 I think wanted to say: when I came i thought you were praying. But its not corret in turkish...

Let me try - but I´m not sure about it, better wait for someone else for confirmation or correct translation:

Geldiðimde, sen namaz kýlýyorsun (or maybe "kýlýyordun" ?) sandým.

 I think our friend wanted translation from Turkish to English...as its the forum post?

Reyhan its fine. I wanted to say it in Turkish, but I always try to construct a sentence nyself.

Thanks guys

 Aha..I understand 

Tomac can you explain how you came to this "Geldiðimde" conclusion. I don´t understand how its works. Thank you so much

It is a way to say "when something happened": (past participle) + -da/-de suffix (in this case "geldiðimde" - "when I came" / if you mean "when you came" it should be "geldiðinde"). Here are few examples from "Manisa Turkish" website and from "Teach yourself Turkish" book:

I feel good when I shower often.

Sýk sýk duþ yaptýðýmda kendimi iyi hissediyorum.

I was very tired when I returned from the party.
Partiden döndüðümde çok yorgundum.

Another way is: (past participle) + zaman:

When I arrive at the station, where will you be?

Ýstasyona geldiðim zaman nerede olacaksýn?

When I got up, it was raining hard.
Yataktan kalktýðým zaman çok yaðmur yaðýyordu.

So, I guess, your sentence could also start with "geldiðim zaman" (instead of "geldiðimde").

However, I´m still a learner, and I´m not sure if my sentence is correct - I hope someone more advanced can check it.

You can find this subject very nice explained in Teach Yourself Turkish at page 182-184. The book you can download from here:  http://www.4shared.com/file/24998546/83ff1897/Teach_Yourself_Turkish.html?cau2=403tNull    If you need I also can send you the audio files from this book

Reyhan thank you