I've never met a bought garlic bread that I've enjoyed very much, so I usually make my own. I'll give you the recipe/method first, then add on the frugal bits.
1 long baguette
1/2 lb butter
4 big fat cloves of fresh garlic
handful of parsley
Put butter on to melt in a pan. Meanwhile, chop parsley finely; peel and chop the garlic finely. When the butter is melted, add to the pan and mix well.
Slice the baguette and lay the slices on a flat oven tray.
Using a pastry brush, brush each slice very generously with the mixture - you'll still have some over, but make sure it's garlicky enough - nothing worse than ungarlicky garlic bread! Place tray of bread in freezer and open freeze it for 24 hours or so. When frozen, put into poly bags or boxes in eg dozens or sixes, whatever suits your needs. Seal bag/box and keep in freezer for about up to 6 months. When needed, pop what you need on to a tray and into a hot oven for 10 minutes+ until golden brown and hot.
Now for the frugal bits: I'm still trying to perfect my baguette technicque, so for the moment, I buy them - for garlic bread, I buy the reduced ones and make it straight away. The one in the picture is a full length French stick, organic, I got for 25p. Hoem grown parsley if you can; butter is own brand, but British, at 88p per 1/2 lb. Home grown garlic, or bought. However you make it, it's still cheaper than the "best" you can buy, and much, much better.
Try and add the parsley if you can - it adds colour and flavour, and if you freeze the surpluse, or keep it in the fridge, the green speckles are an instant giveaway that it's garlic butter so you won't put it in your Victoria Sponge!! LOL