Tim,
From Frescobaldi menu: Tools | Special Characters -- my install has all three of the characters you mention (highlighted in the screen shot). This is the default view shown me when I select this Tool.
Depending on our OS you may find alternatives more useful. If you have a Windows computer, using ALT-Keypad# may prove useful. Once you know them, it's fairly quick, and a short guide will help. For example,
… alt-0133 - elipsis symbol
° alt-0176 - degree sign
• alt-0149 - list bullet
· alt-0183 - middle dot
– alt-0150 - en-dash
— alt-0151 - em-dash
² alt-0178 - superscript 2
³ alt-0179 - superscript 3
© alt-0169 - copyright symbol
ä alt-0228 - umlaut a
ë alt-0235 - umlaut e
ï alt-0239 - umlaut i
ö alt-0246 - umlaut o
ü alt-0252 - umlaut u
ñ alt-0241 - tilde n
ß alt-0223 - German esszet
§ alt-0167 - section symbol
¢ alt-0162 - cent sign
÷ alt-0247 - division sign
± alt-0177 - plus-minus sign
¶ alt-0182 - paragraph symbol
Hope this helps.
