I am wondering if there are no cheap rooms to find in the neighbourhood of Tashkent railway station (as in most places in the world)? I mean less then 20 Euros per room (for a double standard room without breakfast - shared bathroom is no problem -I am not looking for any luxury room)? Thanks.
First option is "Komnata otdiha" next door from the Train station building, the price is start from USD 5 (which is the same in Euro, 5 Euro) or Hotel Green, which is 10 min away from the train Station, the price is 15 Euro, without breakfast, or maybe you can deal with them to get the room for 15 Euro with breakfast.
Yes, of course. I give you 100 % that it will not be the problem to find room at USD 10...15 per night (with or without breakfast) and the price includes all taxes which are necessary. Also do not forget every time to take the registration cards(they are free) to prove your stay.
Tashkent - Komnata Otdixa, ART Hostel, Green B&B.
Samarkand - Bakhodir B&B, Emir
Bukhara - Fatima, Zukhra.
Khiva - Meros, Alibek.

Hey Blackberry13, thanks for your answer. Do you know the location of Green B&B in Tashkent (is it the same as Green House in Dekhanabad St, 23) ?? Thanks again.
16, Chavondoz street (+ 998 71 120 61 71). But better to stay in ART Hostel, location is much better, close to the center.

Also, "Topchan Hostel Tashkent", 1.5km southeast of the train station. $12 for dorm, $28 for double ($18 if one person). Taxes and registration included. Breakfast isn't but available for $2 extra.