as a fellow imbuer, i can just say that i personally buy my relic fragments for 3m for 100. it seems like a lot, and probably is even for a new player, but if you use 100 relic fragments and imbue stuff for people to sell, you will easily make back the 3mil well before you use even half of your stash.
a little self promotion can go a long way. for example, using general chat to tell people you are an imbuer for hire will get you people that are willing to pay decent amounts for you to use your ingredients as it saves them gold and time to collect it all.
i hope this helps