Modified LOOKUP Formula for Excluding Missing Lookup Values

I have an example spreadsheet, but neither file or image attachment seems to be working (maybe someone knows a tip or trick for me, but neither is even giving me the option to select an attachment). In any case, maybe I've explained the problem effectively enough that it will make sense without the visual.

I am using the LOOKUP function to attempt to combine two tables into one table. Both tables (Tables 1 and 2) have the same IDs in one column with the exception of several IDs that do not exist in one table or another.

The desired combined table (Table 3) should have one column for the IDs and two columns for values; one column for values from Table 1 and one column for values from Table 2.

Currently the LOOKUP function is allowing me to add a second value column to Table 1 containing the values from Table 2. However, when (for example) an ID present in Table 1 does NOT exist in Table 2, the LOOKUP function apparently chooses the value of the preceding ID for the ID that is missing in Table 2. It seems that because the ID is not present in Table 2, the LOOKUP function (or a more appropriate formula/function) should instead yield a "0," "error," or something similar in the column for values pulled from Table 2.

I am looking for the simplest way to either combine Tables 1 and 2 into a Table 3 in which either (1) all IDs are present and a '0,' 'error,' etc. is entered into the appropriate value column, or (2) the rows for IDs that are not present in both Tables 1 and 2 are completely absent from Table 3.

I hope that my question makes sense, please let me know if I can clarify anything.

gak67, perfect! That was far easier than I anticipated.

Much thanks for your help!