http://czechoutchannel.blogspot.co.uk/
this blog should give you lots of ideas for resturants and some good ideas on prices. I tend to eat in Hospodas when I am in the city,these are really pub/resturants and most are verygood,certainly I ccan get a good lunch and a beer for 150-300kc depending what I am eating and an evening meal with drinks for 3-500kc per person again depending on waht I am eating.
http://www.prague.net/
this website lists all the major tourist attraction and entrance fees ,a few of them may be a bit out of date but it does give you a ball park fiqure.
http://www.livingprague.com/
this is another excellent informative website and includes some discount vouchers and meal deals in various resturants.

You'll love the Golden Well. I had a friend who stayed there, and she had nothing but good to stay.

I was not wild about too many restaurants, but I can give you information about two i particular.

The Choco Cafe on Liliova (about a 5 min walk from Old Town Square) is fabulous. Be sure to check it out. http://www.choco-cafe.cz/house-of-red-chair_p19.html

Also, if you go to U Prince (They have a location near Charles Bridge and on Old Town Square), make sure you watch what you order and what you get. Rick Steves warns of their tendency to switch orders for a more expensive one. I can tell you honestly that it happened to us. We had to fight to get what we ordered. Also, in very tiny print, they advise you that there is an extra charge for sitting outside. Actually, most OTS restaurants do that, so beware.

Have fun!

Unclegus was right on with his pricing. That is our budget when we go out, unless we are doing a special event dinner.

also, Choco Cafe is excellent.

Just know that prices are much higher in Prague 1 than the other districts. Vinohrady is easy to get to for a dinner, as is much of Prague 6. We rarely eat in Prague 1 anymore.

Recently, in Prague 1, we have enjoyed meals at Clear Head (vegetarian) http://www.lehkahlava.cz/en_novinky.htm and their sister restaurant, Maitrea. Also, Zebra near Mustek, and School Restaurant http://www.school.cz/en

Definitely go to V. Zatisi. It's excellent!

We really enjoyed Katr, http://www.katrrestaurant.cz/o-nas, a very reasonably priced restaurant just a few blocks north of the Old Town Square. For entrees and drinks we spent about 550 CK, very reasonable!

Wow, thanks everybody! I was gone and just rechecked my posts. The Chocolate Cafe sounds great - we enjoyed the hot chocolate at Angelina in Paris so I will check it out. Looked at someof the links as well - I shall have to translate the ones only in Czech, but appreciate the recommendation. Unclegus, thanks for the numbers, that's exactly what I was looking for. I'd like to get more krona here and not use the ATM as much in Prague.

Do any or most places take euros as well as krona? .

some of the places in the city center will take Euros but you will be a terrible exchange rate,for larger ppurchases use your credit card.
I use my atm card whever I travel, always the best exchange rate and a safe way of carrying money.
you will find that most if not all returants will have a english translation to the menu,even further out in the suburnbs it is becoming more common,The lunchtime menus (Denni menu or Denni listek) are usually only in czech but can offer an excellent bargain, usually 2 course (very limited choice) for around 100-125kc.
My cheapest meal on my last trip(late october last year) was in Planeta Zizkov where a goulash with dumplings and a beer cost me 100kc.
where are you staying I might be able to make some suggestions of Hospodas for you.
I am back in the city on the 23rd May for my annual trip too the Czech Beer Festival.

I see you are at the Goldenwell,walk down to Kampa island, a few good places there but I really like the resturant of U Karkla Mosta (Archibald hotel). Uop the hill past the catle are some good place but in the Strahov monastry complex is the Klasterini Pivovar , very good food but they make their own beer that is quite superb, must stopm place for me when in the city,not fine dining but bloody good.

Great suggestions for upcoming trip.