* Lo! (archaic, expressing surprise or excitement)
* Lousy! (expressing annoyance or disappointment)
* Lord! (expressing surprise, shock, or disbelief)
* Look! (used to attract attention to something)
* Lickety-split! (expressing speed or haste)
It's worth noting that some of these are more informal or archaic than others.
Let me know if you'd like to explore other letter-based interjection lists!