If you're looking for teas then I'd recommend allspice. Burning allspice, drinking it as a tea, or applying it to charms are all good ways to increase your luck. Cinnamon is also a good herb for luck and protection either added to your tea or burned as incense. Ginger and sage tea are both used for protection mainly.
As for spells, most practitioners agree that the most effective spell you can cast is the one that you create for yourself. If you're still keen on using another person's spell, though, then there are plenty of luck and protection spells here on this site.
There are a few other methods you can try with the use of herbs if you're interested, such as carrying a salep root or a dried acorn on your person and hanging aloe above your door. You can also create a charm bag and place inside it an acorn, a clover, a pine cone, or some other items. Here is some more information on creating a charm bag: http://sacredwicca.com/charm-bags