Symbology:
Welcome to the board - none to worry about asking basic questions. When it comes down to it, there is nothing that is overly approachable about this field, none of this comes easy - so we fully expect people to ask these sort of questions. The fact is the writing system is quite complicated and was forgotten for some 1800 years. I don't know your level of familiarity with this all of this, generally people who look specifically at contexts like Dilmun, Susa and Jemdat Nasr have been reading for awhile. But just to be safe I will explain things in details, as I say, none of this is intuitive.
Well the suggestion that Sheshki made above is quite ingenious for your purposes, I would think. Using ePSD is the easiest way to get the basic word for i.e. scorpion and at the same time, the cuneiform signs used to write this. What you will get after inputing "scorpion" into the ePSD database is the Old Babylonian sign forms, i.e. how the signs looked around 1900 B.C. or so. For scorpion you end up with this sign:
It sounds to me like you are looking for the earliest sign forms however. This will require an additional step.
Once you type scorpion into ePSD, open the entry - the Sumerian word will be given. In this case, the Sumerian word given is "ĝir " . But they wrote their word "ĝir " with the sign which moden specialists have labeled "ĝir2" . It is important to note what Sumerologists label the relevant signs, not the ĝir sign, or the ĝir3 sign - the ĝir2 sign. You can tell precisely what signs are correct as the ePSD entry will specify this, look for the part in each entry where the "wr." (=written with) is specified. In this entry they specify the ĝir2 sign in the following manner "wr. ĝir2 "
Once you have the specific signs used for the Sumerian word in question - copy the sign value (ĝir2), and search for it at an additional sign list:
www.cdli.ucla.edu/tools/SignLists/protocuneiform/archsigns.htmlFor ĝir2 the following items were found:
Or another variant of the same sign:
This second sign list is a list of archaic signs, signs that come mainly from the site of Uruk, where writing was first invented. These signs come from about 3200 B.C. and are what is called "proto-cuneiform" , they are not technically yet, they are more like stylized drawings made with a sharpened point. This is the true form of mankind's earliest writing. Later these same stylized drawings invented in Uruk would change in the Early Dynastic period, and would be written with the triangular reed stylus in more abstracted forms, becoming the cuneiform writing which Mesopotamia is mainly known for.
Notice in the archaic sign forms, there frequently occur shapes/drawings that are clearly animals or animal heads. You can take the value given for any of these signs at the CDLI list, and copy that value into the ePSD to try and get the dictionary entry and see what animal it was supposed to have been. But there is a problem with this - often, the Sumerians would use a sign not only for what was drawn/represented, but for the sound value to. So if I draw a picture of a monkey, I can use that picture to mean monkey, or I can use that same sign as a short cut to sound out 'mon-day' or for 'key' or for 'mon-ster' , well this is a rough analogy but you know what I mean. So searching the dictionary in this way may mean you will get all sorts of words the sign is connected with for its sound, but none of these signs will have the value of 'monkey' (which you may actually be searching for).
Another way that animal signs could be used is as "Determinatives." So they used the fish signs ku6 after the name of all sorts of fish, to signal that a fish was just spelled out.
There is the archaic ku6 sign. When the sign is used as a determinative, this is sometimes called a "semantic indicator" and is a major feature of cuneiform texts. So they don't just write bahar (the bahar) - they write bahar
ku6 (the bahar (specifically a fish)). If you type ku6 into ePSD a list of fish will come up because they are all marked by the determiner ku6.
My email is bill.mcgrath@utoronto.ca if you may need help working out a process, or you can post technical questions of any sort here as well. If you have access to a book like Rene Labat's "Manuel D'Epigraphie Akkadienne" this shows the archaic signs forms as well as the Old Babylonian in one entry, it has an index and so on. But the webpages mentioned have their own advantages as well. If you would like to put together a list and ask someone here to check it afterward, this is perfectly fine.
I will post more general information about animals in Mesopotamia soon.