Yes, the Dictionary of the Swedish Academy which can be found online here.
If you type in e.g. ta you get the following text, which I can help you decode:
ta äv. åld. taga v. tog, tagit, tagen taget tagna, pres. tar äv. åld. tager, imper. ta äv. åld tag
There you have first the infinitive form then an archaic alternative (äv. åld. means ’also archaic’) then it says ’v.’ (verb) and then the past tense tog the perfect form tagit and then the participles in the en-form, ett-form and the plural tagen taget tagna, then it says the present tense tar or archaically tager and the imperative ta or the archaic tag.
If you look up a regular verb like leta (look for) you will only get this:
leta v. –de
Which means that the past tense is the regular letade and then the other forms are also regular, i.e. letat in the perfect, letar in the present etc. If you do the same for söka (search) you get
söka v. sökte
Which means that it’s sökte in the past tense, and then it has to be söker in the present tense and sökt in the perfect, and sök in the imperative, since that’s how regular verbs with that ending go.
If you look up a noun like hund (dog) you get:
hund s. –en –ar
Which means that it’s regular, the definite form is hunden (so it’s an en-word) and the plural is hundar.
If you type in a more irregular noun like far (father) you get:
far el. fader s. fadern; pl. fäder, best. pl fäderna äv. åld. fädren
That is, far or fader; plural fäder, definite form plural fäderna or archaic fädren.
Wow! It took me a while to get to the dictionary: Here is a more direct link: http://g3.spraakdata.gu.se/saob/
Edit: answer to below Your link gives me error messages. Thank you for the newer link. Are they different kinds of dictionaries? What do those acronyms stand for?
I think I found it: http://www.svenskaakademien.se/svenska-spraket/svenska-akademiens-ordlista-saol I am still not in the right place, when I try to look up the word: http://www.svenskaakademien.se/search/node/ta You tell us to type in for example "ta" and then it says that "You must have at least one positive keyword with 3 characters or more."
What do you click on to get there? None of these are very easy to use for an English speaker that is trying to learn Swedish.